Drafting instrument



Patented Apr. 24, 1923.

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ROBERT RUFFIN, JR., OF SENATOBIA, IVIISSISSIPPI.

DRAFTING INSTRUMENT.

Application filed June 21,

T all w hom it may concern.'

Be it known that I, ROBERT RUFFIN, Jr., a citizen ot' the United States, residing at i Senatobia, in the county of Tate and State invention appertains.

Although a `preferred embodimento'l the invention is depicted in the drawings, and hereinafter described, it will be understood that an instrument maker, working within the scope of what is claimed, may alter the structure shown, as to its precise form, without departing from the spirit of the invention or avoiding the charge ot infringement.

In the drawings y Figure 1 shows in plan, an instrument constructed in accorda-nce with the invention: Figure2 is a View showing a sample of the iield notes tobe platted.

The instrument forming the subject matter of this application is fashioned from Celluloid, paper, metal 0r any other thin material and embodies a frame 1, including a top strip 2, a bottom strip 3, end members l connecting the strips, an intermediate rib 5 connecting the strips, lateral ribs 6, 7 and 8 connecting the strips, and located at one side of the intermediate rib 5, and lateral ribs 9 connecting the strips and located on the opposite side of the rib 5 from the ribs 6, 7 and 8. The top strip 2 has an inner fiducial edge 10, the ribs 9, 5, 6, 7 and 8 being spaced apart and being located at right angles to the iiducial edge 10. The top strip 2 is calibrated as at 11, in opposite directions, from a zero point 12 alined with a longitudinal slot 14 formed in the inter` mediate rib 5, the rib 5 being calibrated on opposite sides of the slot, and the ribs 6, 7, 8 and 9, together with the end members 4 being calibrated, likewise, as shown at 15, from a zero point indicated at 16 and coinciding with the iducial edge of the top strip 2. The bottom strip 3 may be calibrated in opposite directions, as at 17, from a zero point 18 alined with the slot 14 in the intermediate rib 5. The bottom strip 3 has an inner iducial edge 19, which, cooper- 1922; serial No. 569,838.

ating 'with the slot 14 in the rib 5, deines a center 21 from which radiate protractor marks located on the top strip 2 and the end members 4:. A few of the protractor marks 20, only, are shown, for the sake of clearness, but there may be as many of them as is considered expedient. The protractor marks vafford, obviously, a. means whereby anglesniay be laid off withy the edge 19 of the bottom strip 3 as a line of reference.

In Figure 2 there is shown a set of field notes which, let it be supposed, are to be platted. The column 22 is 'for thestations.

The plus rod readings are entered in the rolumn 23. The column24 is adapted to receive the minus rod readings. The heighty y ot the instrument is entered in column 25. The elevation of thevarious points is noted in column 26. Column 27 isv for they elevation of the grade line. The cut may be marked in column 28 and the till in column 29. The notes above alluded to are for illustration, merely, the engineer keeping his notes in such i'iorm as his taste may dictate.

The device forming the subject matter of this application is adapted to be used in connection with `cross section paper, for laying out aline representing the contour of the ground at any cross section in earth work.

The slot 14 in the rib 5 is made to coincide with any line on the cross section paper which has been selected to represent the Vertical central line oi' the cross section. The iiducial edge 10 or the strip k2 is brought into coincidence with the line on the cross section paper which. has been fixed upon as representing the height of the instrument.

Suppose that the operator intends to plat the cross section at station 17 noted in column 22 of the notes. At the center line of the cross section at this station there is a minus rod reading of 6.5, as shown' in vcolumn 24. This distance is read off on one of the scales or' the intermediate rib 5, and a dot is made at the proper place on the cross section paper, through the slot 14. Suppose that the next rod reading was taken at a distance of live feet to the right, as shown in column 22. This distance is read oil' to the right on the scale 11, and the minus rod reading of 7.5 is read ott on the scale of the rib 6, a dot being made on the cross section paper at the proper place. In the same way, a minus rod reading of 8.0 at ten feet to the right of the traverse may be read oif from the scale on the rib 7, and a mark made on the paper. In the same Way, the rod readings to the left or' the traverse may be platted by means of the scales on the ribs 9. After the rod readings have been entered properly on the paper, as above described, the dots on the paper may be connected by a line indicating the contour o the ground, and after the shape of the earth prism has been iixed and laid down, the cross sectional area may be taken off by means oit' a planimeter, or in any other Way.

If the cuts are given, as indicated in column 28, instead of the rod readings, the idncial edge l0 of the top strip 2 is set at the grade line on the papeigshown by the entry in column 27 of the notes, and, then, the cuts, indicated in column 28, are platted as hereinbefore described in connection With the rod readings.

l. An instrument for platting cross sections in earth Work, comprising a frame including top and bottom strips, an inter mediate rib connecting the strips, and lateral ribs connecting` the stripsl and located on opposite sides of the intermediate rib, one of the strips having an inner iiducial edge, the ribs being spaced apart and being located at right angles to the iducial edge, one of the strips being calibrated in opposite directions irom a zero point coinciding With the intermediate rib, all of the ribs being calibrated longitudinally from a zero point coincidinfr With the fiducial edge.

2. n instrument for platting cross sections in earth Work, comprising a frame including top and bottom strips, an intermediate rib connecting the strips, and lateral ribs connecting ,the strips and located on opposite sides of the intermediate rib, the intermediate rib having a longitudinal slot, the top strip having an inner iducial edge, the ribs being spaced apart and being located at right angles to the iiducial edge, the top strip being calibrated in opposite directions from a zero point coinciding With the slot, and all of the ribs being calibrated longitudinally from a Zero point coinciding with the ducial edge.

In testimony that I claim the foregoing as my own, I have hereto aliXed my signa.- ture in the presence of two Witnesses.

ROBERT RUFFIN, Jn.

Witnesses:

HERBERT HOLMES 

